U.S. patent application number 11/303366 was filed with the patent office on 2006-06-29 for occupant protection system.
This patent application is currently assigned to Takata Corporation. Invention is credited to Hiromichi Yoshikawa.
Application Number | 20060138816 11/303366 |
Document ID | / |
Family ID | 36195937 |
Filed Date | 2006-06-29 |
United States Patent
Application |
20060138816 |
Kind Code |
A1 |
Yoshikawa; Hiromichi |
June 29, 2006 |
Occupant protection system
Abstract
An occupant protection system is provided in which gas from a
gas generator flows through a duct and into an airbag smoothly even
with a gas generator that emits a jet of gas in non-axial
directions relative to the duct. The airbag disposed under a seat
cushion and the gas generator are joined together with the duct. In
one form, the duct is fitted on the nozzle of the gas generator, so
that the inner circumferential surface of the duct faces gas ports
around the side circumferential surface of the nozzle. When the gas
generator emits a jet of gas, the gas from the gas generator issues
from the gas ports radially relative to the nozzle, and then
strikes against the inner circumferential surface of the duct to
change in direction, thus flowing along the axis of the duct.
Inventors: |
Yoshikawa; Hiromichi;
(Inukami-gun, JP) |
Correspondence
Address: |
FITCH EVEN TABIN AND FLANNERY
120 SOUTH LA SALLE STREET
SUITE 1600
CHICAGO
IL
60603-3406
US
|
Assignee: |
Takata Corporation
Minato-ku
JP
|
Family ID: |
36195937 |
Appl. No.: |
11/303366 |
Filed: |
December 16, 2005 |
Current U.S.
Class: |
297/216.1 ;
180/271; 280/748 |
Current CPC
Class: |
B60R 21/26 20130101;
B60R 2021/2612 20130101; B60N 2/42718 20130101 |
Class at
Publication: |
297/216.1 ;
180/271; 280/748 |
International
Class: |
B60N 2/42 20060101
B60N002/42; B60R 21/02 20060101 B60R021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 25, 2005 |
JP |
2005-310159 |
Dec 24, 2004 |
JP |
2004-373960 |
Claims
1. An occupant protection system comprising: a seat airbag for
lifting a vehicle seat with airbag inflation; a gas generator
outside of and spaced from the seat airbag, the gas generator
generating hot inflation gas for inflating the airbag in vehicle
emergency conditions; an elongate duct extending outside the seat
airbag and between the seat airbag and the gas generator for
delivering inflation gas to the airbag with the inflation gas
flowing axially through the elongate duct and axially out from the
duct into the airbag.
2. The occupant protection system of claim 1 wherein the gas
generator has a nozzle portion including at least one gas port that
is outside the airbag.
3. The occupant protection system of claim 1 wherein the duct
includes an inlet portion, and the gas generator nozzle portion and
duct inlet portion have cooperating structure to secure the duct to
the gas generator outside and spaced from the airbag.
4. The occupant protection system of claim 2 wherein the duct and
the gas generator are interconnected by a cap or adapter
member.
5. The occupant protection system of claim 4 wherein the cap or
adapter member and the gas generator nozzle portion, and the cap or
adapter member and the duct have cooperating structure to secure
the duct to the gas generator with the cap or adapter member
extending therebetween outside and spaced from the airbag.
6. The occupant protection system of claim 1 wherein the gas
generator and the elongate duct have a flange connection
therebetween that is outside the airbag.
7. The occupant protection system of claim 1 wherein the gas
generator and the elongate duct have a threaded connection
therebetween that is outside the airbag.
8. The occupant protection system of claim 1 wherein the gas
generator has a nozzle including a base portion for mounting the
elongate duct thereto, and at least one gas port for emitting gas
therefrom.
9. The occupant protection system of claim 1 wherein the elongate
duct has an outlet end and the airbag has an inlet socket with the
duct outlet and the airbag socket configured to receive the axial
flow of inflation gas from the duct in the same direction into the
airbag for smooth inflation gas flow into the airbag.
10. A vehicle seat airbag system comprising: a vehicle seat having
a seat cushion; an airbag disposed under the seat cushion; a gas
generator for generating inflation gas to inflate the airbag and
lift up the seat cushion in emergency conditions; a nozzle portion
of the gas generator having gas ports arranged to emit inflation
gas generally radially therefrom; and a duct extending between the
nozzle portion to the airbag under the seat cushion to redirect the
gas flowing generally radially from the gas generator nozzle
portion to flow axially in the duct and into the airbag for smooth
inflation gas flow into the airbag.
11. The vehicle seat airbag system of claim 10 wherein the duct has
an elongate tubular wall of predetermined length with the tubular
wall extending for substantially the entire length thereof outside
of the airbag.
12. The vehicle seat airbag system of claim 10 wherein the duct has
an elongate, bent configuration.
13. The vehicle seat airbag system of claim 10 wherein the duct has
an inlet end and an outlet end spaced from each other so the inlet
end is outside the airbag.
14. The vehicle seat airbag system of claim 13 wherein the duct
inlet end and the gas generator nozzle portion have one of a
flanged and threaded connection therebetween.
15. The vehicle seat airbag system of claim 13 wherein the duct
inlet end and the gas generator nozzle portion have a cap or
adapter member connected therebetween that is outside the
airbag.
16. The vehicle seat airbag system of claim 15 wherein the adapter
member has inlet and outlet chambers and a partition wall
therebetween having at least one gas opening therein configured so
that inflation gas radially emitted into the inlet chamber flows
through the gas opening into the outlet chamber in a generally
axial direction.
17. The vehicle seat airbag system of claim 10 wherein the gas
generator and the duct are under the seat cushion.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an occupant protection
system for protecting an occupant of a vehicle such as a car in the
event of a collision and, more particularly, it relates to an
occupant protection system that restrains the waist of an occupant
to prevent the body of the occupant from moving forward and
downward in a front collision.
BACKGROUND OF THE INVENTION
[0002] As a system for protecting an occupant in the event of a car
collision, Japanese Unexamined Patent Application Publication No.
10-217818 describes an occupant protection system in which an
inflatable airbag is disposed between a seat cushion and a seat
pan, and the front part of the seat cushion is pushed up by
inflating the airbag in a car collision to prevent a submarine
phenomenon such that the occupant passes under a lap belt in a
front collision, even with a seatbelt in use.
[0003] FIG. 6 is a longitudinal sectional view of the occupant
protection system of the reference, along the length of the seat.
An airbag 44 is disposed between a cushion frame 40 and a seat pad
42 in the front of the seat. The airbag 44 extends along the
lateral width of the seat and is inflated by an inflator (gas
generator) 46. The upper surface of the seat pad 42 is covered with
a trim cover 48, on which an occupant sits.
[0004] When the inflator 46 is activated in case of a vehicle
collision, the airbag 44 inflates, so that the front part of the
seat pad 42 is pushed up or tossed from below to increase in
density, thereby preventing the forward movement of the body of an
occupant (including restraining).
[0005] While the inflator (gas generator) 46 is disposed in the
airbag 44 in the reference, the gas generator can be disposed
outside the airbag to moderate the heat-resistance requirement for
the airbag. In this case, the gas generator and the airbag are
joined together with a duct, through which gas from the gas
generator is introduced into the airbag.
[0006] In joining a gas generator with a duct, the gas generator is
preferably of a type having a gas port at the distal end. This type
of gas generator generally has the gas port at the side
circumferential surface of the distal end. In this case, when the
gas generators emit a jet of gas, the gas issues out from the
distal end of the gas generators radially, or in non-axial
directions relative to the duct, so that the gas flows less
smoothly into the depth in the airbag (a portion furthermost from
the duct).
SUMMARY OF THE INVENTION
[0007] Accordingly, it is an object of the present invention to
provide an occupant protection system in which the gas from a gas
generator flows into the airbag smoothly even with a gas generator
that emits a jet of gas in non-axial directions relative to the
duct.
[0008] An occupant protection system according to one aspect of the
present invention includes an airbag disposed under the front part
of a seat cushion and inflatable so as to push the front part of
the seat cushion from below; a gas generator that inflates the
airbag in an emergency of a vehicle; and a duct that introduces gas
from the gas generator into the airbag, wherein the gas from the
gas generator issues in non-axial directions relative to the duct
and then flows along the axis in the duct.
[0009] In the occupant protection system according to the
invention, when a vehicle gets into an emergency such as a
collision, the gas generator emits a jet of gas, and the gas from
the gas generator is introduced into the airbag through the duct to
inflate the airbag. The seat cushion is pushed up or tossed from
below by the inflated airbag to increase in density (or to be
hardened), thereby preventing the forward movement of the waist of
the occupant in the seat.
[0010] In the occupant protection system, even with a gas generator
that emits a jet of gas in non-axial directions relative to the
duct, the gas from the gas generator issues in the non-axial
directions relative to the duct and then flows in the duct along
the axis. Thus, the gas from the gas generator flows smoothly into
the depth of the airbag (a portion furthermost from the duct)
through the duct. Accordingly, the entire airbag inflates to
restrain the occupant at an early stage.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Embodiments of the present invention will be described
hereinbelow with reference to the drawings, of which:
[0012] FIG. 1 is a perspective view of the frame of a seat
including an occupant protection system according to an embodiment
of the present invention;
[0013] FIG. 2 is an exploded perspective view of the gas generator,
the duct, and the airbag of the occupant protection system in FIG.
1;
[0014] FIG. 3 is a cross-sectional view of the joint portion of the
duct and the gas generator of the occupant protection system in
FIG. 1;
[0015] FIG. 4 is a cross-sectional view of the joint structure of
the duct and the gas generator of an occupant protection system
according to another embodiment;
[0016] FIG. 5 is a cross-sectional view of the joint structure of
the duct and the gas generator of an occupant protection system
according to still another embodiment;
[0017] FIG. 6 is a sectional view of an occupant protection system
of a related art;
[0018] FIG. 7 includes sectionals views of the joint structure of a
duct and a gas generator according to another embodiment; and
[0019] FIG. 8 is a sectional view of the joint structure of a duct
and a gas generator according to yet another embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] FIG. 1 is a perspective view of the frame of a seat
including an occupant protection system according to an embodiment
of the present invention. FIG. 2 is an exploded perspective view of
the gas generator, the duct, and the airbag of the occupant
protection system. FIG. 3 is a cross-sectional view of the joint
portion of the duct and the gas generator.
[0021] The frame of a car seat includes a base frame 1 and a back
frame 4 rotatably joined to the base frame 1 via a support shaft 2
and a reclining device (not shown). A headrest 6 is mounted to the
upper part of the back frame 4. The base frame 1 includes left and
right side frames 1a and 1b. A seat pan 8 is disposed between the
front parts of the side frames 1a and 1b.
[0022] Although not shown, the base frame 1 and the back frame 4
mount a seat cushion and a seat back made of urethane or the like.
The seat pan 8 is disposed under the front of the seat cushion.
Reference numeral 1d in FIG. 1 denotes a spring that supports the
seat cushion.
[0023] An occupant protection system 10 includes an inflatable
airbag 12 disposed on the seat pan 8 (under the front of the seat
cushion), a gas generator 14 for inflating the airbag 12, and a
duct 16 for introducing gas from the gas generator 14 into the
airbag 12.
[0024] The airbag 12 extends along the lateral width of the seat
pan 8 (along the width of the vehicle), right and left opposite
ends of the airbag 12 being each fixed to the upper surface of the
seat pan 8 with a bolt 18. Reference numeral 12a in FIG. 2 denotes
bolt insertion holes provided at the right and left ends of the
airbag 12. Each bolt 18 is screwed into the seat pan 8 through the
bolt insertion holes 12a.
[0025] As shown in FIG. 2, the airbag 12 has a duct socket 20 at
one end, into which one end of the duct 16 is inserted. The duct
socket 20 is secured to the duct 16 with a band 22.
[0026] As shown in FIG. 2, the gas generator 14 includes a columnar
main body 24 containing a gas generator, a tubular nozzle (gas
port) 26 projecting from a first end (distal end) of the main body
24, and an initiator (gas-generator ignitor) 28 disposed at a
second end of the main body (rear end) 24. Numeral 28a indicates a
harness for passing electric current to the initiator 28.
[0027] As shown in FIG. 3, the distal end of the nozzle 26 is
closed, around the side circumferential surface of which multiple
gas ports 30 are provided at intervals. As shown in the drawing,
the nozzle 26 is smaller in diameter than the inside diameter of
the second end of the duct 16. Around the base end of the nozzle
26, a pair of duct-connecting flanges 32a and 32b (they are
indicated by numeral 32 in FIG. 2) is provided along the axis of
the nozzle 26 at intervals.
[0028] The second end of the duct 16 is fitted on the nozzle 26.
The inner circumferential surface of the duct 16 faces the gas
ports 30 around the side circumferential surface of the nozzle
26.
[0029] The second end of the duct 16 connects to the flanges 32a
and 32b. In connection, the second end of the duct 16 is fitted
onto the vicinity of the base end of the nozzle 26 (close to the
base end relative to the flanges 32a and 32b) and then the end of
the duct 16 is crimped or squeezed to be brought into close contact
with the outer circumferential surface of the flanges 32a and 32b.
At that time, the middle of the duct 16 is also brought into
between the flanges 32a and 32b. Thus the second end of the duct 16
is connected to the flanges 32a and 32b.
[0030] As shown in FIG. 1, the gas generator 14 is placed on the
seat pan 8 with the axis along the lateral width of the seat pan
8.
[0031] When a vehicle including the occupant protection system 10
with such a structure gets into an emergency such as a collision,
the gas generator 14 emits a jet of gas, and the gas from the gas
generator 14 is introduced into the airbag 12 through the duct 16
to inflate the airbag 12. The seat cushion is pushed up or tossed
from below by the inflated airbag 12 to increase in density (or to
be hardened), thereby preventing the forward movement of the waist
of the occupant in the seat.
[0032] In this occupant protection system 10, the duct 16 is fitted
on the nozzle 26 of the gas generator 14, so that the inner
circumferential surface of the duct 16 faces the gas ports 30
around the side circumferential surface of the nozzle 26.
Accordingly, when the gas generator 14 emits a jet of gas, the gas
from the gas generator 14 issues radially from the gas ports 30
relative to the nozzle 26, and then strikes against the inner
circumferential surface of the duct 16 to change in direction, thus
flowing along the axis of the duct 16.
[0033] The gas from the gas generator 14 thus flows smoothly
through the duct 16 into the depth of the airbag 12 (a portion
furthermost from the duct 16). As a result, the entire airbag 12
inflates to restrain the occupant at an early stage.
[0034] According to the embodiment, the duct-connecting flange 32
(32a and 32b) is provided at the base end of the nozzle 26 of the
gas generator 14, to which the duct 16 is secured by crimping or
squeezing, thereby joining the duct 16 and the gas generator 14
together. The joint structure of the duct and the gas generator may
be another.
[0035] FIG. 4 is a cross-sectional view showing another joint
structure of the duct and the gas generator.
[0036] In this embodiment, at the base end of the nozzle 26 of the
gas generator 14 is provided a large-diameter portion having an
outer diameter substantially equal to the inner diameter of the
duct 16. The large-diameter portion has a male screw 34a around the
outer circumferential surface thereof. A female screw 16a that is
to be screwed onto the male screw 34a is provided around the inner
circumferential surface of the end of the duct 16.
[0037] According to this embodiment, the nozzle 26 is inserted into
the duct 16 to screw the male screw 34a into the female screw 16a;
thus the gas generator 14 and the duct 16 are joined together.
[0038] The other structure of the embodiment is the same as that of
the embodiment in FIGS. 1 to 3; the same numerals as those of FIGS.
1 to 3 indicate the same components.
[0039] FIG. 5 is a cross-sectional view of still another joint
structure of the duct and the gas generator.
[0040] According to this embodiment, at the end of the gas
generator 14 is placed a head cap 36 that surrounds the nozzle 26.
The head cap 36 connects to the duct 16.
[0041] Also in this embodiment, at the base end of the nozzle 26 is
provided a large-diameter portion 34 substantially equal in an
outer diameter to the inner diameter of the opening at the rear of
the head cap 36. Around the side circumferential surface of the
large-diameter portion 34 is provided a male screw 34a. Around the
inner circumferential surface of the rear opening of the head cap
36 is provided a female screw 36a that is to be screwed on the male
screw 34a. The head cap 36 is placed on the nozzle 26 and the male
screw 34a is screwed into the female screw 36a; thus, the head cap
36 is fixed to the end of the gas generator 14.
[0042] In the end face of the head cap 36 is provided an opening
36b. A collar 36t is provided around the inner rim of the opening
36b, through which a duct 16B passes. Around the outer rim of the
end of the duct 16B is provided a flange 16b. The flange 16b is
placed on the collar 36t from the inside of the head cap 36 and
fixed together by welding or the like.
[0043] The other structure of the embodiment is the same as that of
the embodiment in FIGS. 1 to 3.
[0044] According to this embodiment, when the gas generator 14
emits a jet of gas, the gas from the gas generator 14 first issues
into the head cap 36, and then flows into the duct 16B through the
head cap 36. Thus, also in this embodiment, the gas from the gas
generator 14 flows in the duct 16B along the axis of the duct 16B.
The gas therefore flows smoothly into the depth of the airbag 12
through the duct 16B.
[0045] FIG. 7(a) is a longitudinal sectional view showing the joint
structure of a gas generator and a duct according to another
embodiment; and FIG. 7(b) is a cross-sectional view taken along
line B-B of FIG. 7(a).
[0046] The gas generator 14A includes, like the gas generator 14,
an approximately columnar main body 24A and a cylindrical nozzle
26A projecting from the distal end of the main body 24A. The nozzle
26A is sealed at the end face, and has multiple gas ports 30A
around the side circumference. A male-screw axial rod 38 projects
from the distal end of the nozzle 26A.
[0047] The gas generator 14A and the duct 16 are joined together
via an adapter 50. The adapter 50 includes a cylinder 52, a
partition wall 54 disposed in the vicinity of the axial center in
the cylinder 52 with the plate surface disposed radially, a central
hole 56 disposed in the center of the partition wall 54, and
multiple gas openings 58 around the central hole 56 of the
partition wall 54.
[0048] The adapter 50 and the gas generator 14A are joined together
in such a manner that the male-screw axial rod 38 is inserted into
the central hole 56 of the adapter 50, and a nut 60 is tightened to
the male-screw axial rod 38, with the base end of the cylinder 52
fitted around the main body 24A of the gas generator 14A via a
packing 62 such as an O ring. A female screw 50a is cut around the
inner circumference of the distal end of the cylinder 52. The male
screw 16a' of the duct 16 is screwed into the female screw 50a, so
that the duct 16 is joined to the gas generator 14A via the adapter
50.
[0049] In FIG. 7, the packing 62 is interposed between the inner
circumference of the cylinder 52 and the outer circumference of the
main body 24A of the gas generator 14A. Alternatively, like an
adapter 50A of FIG. 8, a collar 64 may be provided around the inner
circumference of the cylinder 52, and a packing 66 may be
interposed between the collar 64 and the distal end face of the
main body 24A.
[0050] The other structure of FIG. 8 is the same as that of FIG.
7(a), wherein the same reference numerals indicate the same
components.
[0051] In FIGS. 7 and 8, the duct 16 is joined to the cylinder 52
via the male screw 16a'. Alternatively, it is possible to provide a
flange similar to the flange 16b of the duct 16B in FIG. 5 at the
distal end of the duct 16, provide a collar similar to the collar
36t of the head cap 36 in FIG. 5 at the distal end of the cylinder
52, and join the adapter 50A and the duct 16 together by bringing
the flange and the collar into engagement with each other.
[0052] It is to be understood that the foregoing embodiments are
only examples of the invention and the invention is not limited to
the foregoing embodiments.
* * * * *